Conformational analysis of natural products

Pseudorotation in b-ribose


Use the form below to calculate the proton-proton coupling constants in β-ribofuranosides (or nucleosides/nucleotides) form the puckering phase or to determine the puckering phase from experimental coupling constants.
Note that there might be more than one phase that reproduces the experimental couplings but only one is found by the program. A rmsd > 0.5 suggests that there is a conformational equilibrium between two conformers (i.e. north (3'E) ↔ south (2'E)).
For comparison an equilibrium between north and south conformers is also calculated. If the ribofuranose ring is rigid then the rmsd for the fitted pseudorotaion angle should be lower than for the two state model.
To calculate the coupling constant just enter the pseudorotation angle (P) in degrees or select a conformer by pressing the appropriate button below.

Pseudorotation angle (P) = °
...or select a conformer

H1'-H2' = Hz Hz
H2'-H3' = Hz Hz
H3'-H4' = Hz Hz
C1'-H3' = Hz Hz
C1'-H4' = Hz Hz
C2'-H4' = Hz Hz
Best P rmsd
Best N ↔ S equilibrium %N (3'E) rmsd